Three-Dimensional (3D) Image System and Electronic Device

ABSTRACT

The present application provides a three-dimensional (3D) image system, comprising a structural light module, configured to emit a structural light, wherein the structural light module comprises a first light-emitting unit, the first light-emitting unit receives a first pulse signal and emits a first light according to the first pulse signal, a duty cycle of the first pulse signal is less than a specific value, an emission power of the first light-emitting unit is greater than a specific power, and the first light has a first wavelength; and a light-sensing pixel array, configured to receive a reflected light corresponding to the structural light.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a divisional application of U.S. patentapplication Ser. No. 15/959,272, filed on Apr. 22, 2018, which is acontinuation of international application No. PCT/CN2017/097332, filedon Aug. 14, 2017. The entire disclosures of these applications are allhereby incorporated herein by reference in their entireties.

FIELD OF THE INVENTION

The present application relates to a three-dimensional (3D) image systemand an electronic device, and more particularly, to a 3D image systemand an electronic device capable of withstanding ambient light.

BACKGROUND

With the rapid development of science and technology, obtainingthree-dimensional (3D) information of the object has been applied in awide range of applications, such as human-computer interaction, 3Dprinting, reverse engineering, 3D reconstruction artifacts. The 3Dstructured light measuring technology, as a non-contact 3D informationacquisition technology, due to its simple, fast and high precision, hasbeen widely used.

Basic idea of the 3D structured light measuring method is to use theprojection of the structured light and its geometry relationship toobtain the 3D information of an object. Firstly, a projecting device isused to project a coded structural light pattern onto the object, and acamera is used to capture the projected image. Secondly, matchingbetween the captured image and the structural light pattern isperformed, and a matching point is obtained. Finally, the 3D informationis solved according to the triangular relationship of the projectingpoint, the matching point and the object.

However, the structural light in the prior art is easily to beinterfered by the ambient light, and an accuracy of the 3D informationis degraded. Therefore, it is necessary to improve the prior art.

SUMMARY

It is therefore a primary objective of the present application toprovide a 3D image system and an electronic device capable ofwithstanding ambient light, to improve over disadvantages of the priorart.

To solve the problem stated in the above, an embodiment of the presentapplication provides a three-dimensional (3D) image system, comprising astructural light module, configured to emit a structural light, whereinthe structural light module comprises a first light-emitting unit, thefirst light-emitting unit receives a first pulse signal and emits afirst light according to the first pulse signal, a duty cycle of thefirst pulse signal is less than a specific value, an emission power ofthe first light-emitting unit is greater than a specific power, and thefirst light has a first wavelength; and a light-sensing pixel array,configured to receive a reflected light corresponding to the structurallight.

For example, the duty cycle of the first pulse signal is less than 1/50.

For example, the emission power of the first light-emitting unit isgreater than 4 watts.

For example, the structural light module comprises a diffraction unit,and the diffraction unit forms a diffraction effect on the first lightand generates the structural light.

For example, the diffraction unit is a diffraction optical element.

For example, the light-sensing pixel array comprises a plurality oflight-sensing pixel circuits, and a light-sensing pixel circuit of theplurality of light-sensing pixel circuits comprises a light-sensingcomponent; a first photoelectric readout circuit, coupled to thelight-sensing component, configured to output a first output signal; anda second photoelectric readout circuit, coupled to the light-sensingcomponent, configured to output a second output signal; wherein a pixelvalue corresponding to the light-sensing pixel circuit is a subtractionresult of the first output signal and the second output signal.

For example, the first photoelectric readout circuit comprises a firsttransmission gate, coupled to the light-sensing component; a firstoutput transistor, coupled to the first transmission gate; and a firstread transistor, coupled to the first output transistor, configured tooutput the first output signal; and the second photoelectric readoutcircuit comprises a second transmission gate, coupled to thelight-sensing component; a second output transistor, coupled to thesecond transmission gate; and a second read transistor, coupled to thesecond output transistor, configured to output the second output signal.

For example, the first transmission gate is conducted when the firstlight-emitting unit emits light, the second transmission gate isconducted when the first light-emitting unit does not emit light, and aconduction time interval of the first transmission gate is longer thanan emitting time interval of the first light-emitting unit.

For example, the light-sensing pixel circuit comprises a first resettransistor and a second reset transistor, the first reset transistor iscoupled to the first transmission gate, and the second reset transistoris coupled to the second transmission gate.

For example, the duty cycle of the first pulse signal is time variant.

For example, the structural light module comprises at least a secondlight-emitting unit, the at least a second light-emitting unit receivesat least a second pulse signal and emits at least a second lightaccording to the at least a second pulse signal, a duty cycle of the atleast a second pulse signal is less than the specific value, an emissionpower of the at least a second light-emitting unit is greater than thespecific power, and the at least a second light has at least a secondwavelength, respectively.

For example, the light-sensing pixel array comprises a plurality oflight-sensing pixel circuits, and a light-sensing pixel circuit of theplurality of light-sensing pixel circuits comprises a light-sensingcomponent; a first photoelectric readout circuit, coupled to thelight-sensing component, configured to output a first output signal; atleast a second photoelectric readout circuit, coupled to thelight-sensing component, configured to output at least a second outputsignal; and a third photoelectric readout circuit, coupled to thelight-sensing component, configured to output a third output signal;where a pixel value corresponding to the light-sensing pixel circuit isa sum of the first output signal and the at least a second output signalminus a product of the third output signal and a number of the firstoutput signal and the at least a second output signal.

For example, the first photoelectric readout circuit comprises a firsttransmission gate, coupled to the light-sensing component; a firstoutput transistor, coupled to the first transmission gate; and a firstread transistor, coupled to the first output transistor, configured tooutput the first output signal; a second photoelectric readout circuitof the at least a second photoelectric readout circuit comprises asecond transmission gate, coupled to the light-sensing component; asecond output transistor, coupled to the second transmission gate; and asecond read transistor, coupled to the second output transistor,configured to output the second output signal; and the thirdphotoelectric readout circuit comprises a third transmission gate,coupled to the light-sensing component; a third output transistor,coupled to the third transmission gate; and a third read transistor,coupled to the third output transistor, configured to output the thirdoutput signal.

For example, the first transmission gate is conducted when the firstlight-emitting unit emits light, the at least a second transmission gateof the at least a second photoelectric readout circuit is conducted whenthe at least a second light-emitting unit emits light, the thirdtransmission gate is conducted when the first light-emitting unit andthe at least a second light-emitting unit do not emit light, aconduction time interval of the first transmission gate is longer thanan emitting time interval of the first light-emitting unit, and anconduction time interval of the at least a second transmission gate islonger than an emitting time interval of the at least a secondlight-emitting unit.

For example, the light-sensing pixel circuit comprises a first resettransistor, at least a second reset transistor and a third resettransistor, the first reset transistor is coupled to the firsttransmission gate, the at least a second reset transistor is coupled tothe at least a second transmission gate of the at least a secondphotoelectric readout circuit, and the third reset transistor is coupledto the third transmission gate.

For example, a time in which the first transmission gate is conductedand a time in which the second transmission gate is conducted areseparated by a time blank.

For example, the first wavelength and the at least a second wavelengthare different.

For example, the duty cycles of the first pulse signal and the at leasta second pulse signal are time variant.

The light-emitting unit within the structural light module of thepresent application receives the pulse signal, which is pulse modulated,and emits instantaneous strong light, such that the emitted structurallight has immunity against the ambient light, to improve overdisadvantages of the prior art.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of three-dimensional (3D) image systemaccording to an embodiment of the present application.

FIG. 2 is a schematic diagram of a light-sensing pixel circuit accordingto an embodiment of the present application.

FIG. 3 is a timing diagram of the light-sensing pixel circuit in FIG. 2.

FIG. 4 is a schematic diagram of a 3D image system according to anembodiment of the present application.

FIG. 5 is a schematic diagram of a light-sensing pixel circuit accordingto an embodiment of the present application.

FIG. 6 is a timing diagram of the light-sensing pixel circuit in FIG. 5.

FIG. 7 is a schematic diagram of a structural light according to anembodiment of the present application.

FIG. 8 is a schematic diagram of a structural light according to anembodiment of the present application.

FIG. 9 is a schematic diagram of an electronic device according to anembodiment of the present application.

FIG. 10 is a schematic diagram of a structural light module according toan embodiment of the present application.

FIG. 11 is a schematic diagram of a light-sensing pixel circuit

FIG. 12 illustrates waveforms of pulse signals and transmission gatesignals of different electronic devices.

DETAILED DESCRIPTION

In order to make the objects, technical solutions and advantages of thepresent invention become more apparent, the following relies on theaccompanying drawings and embodiments to describe the present inventionin further detail. It should be understood that the specific embodimentsdescribed herein are only for explaining the present invention and arenot intended to limit the present invention.

To solve the problem of the structural light in the prior art beingeasily to be interfered by the ambient light, the present applicationutilizes a pulse modulated signal to generate the structural light.Specifically, please refer to FIG. 1. FIG. 1 is a schematic diagram of athree-dimensional (3D) image system 10 according to an embodiment of thepresent application. The 3D image system 10 comprises a structural lightmodule 12_t and a camera module 12_r. The structural light module 12_tis configured to generate a structural light SL, and project thestructural light SL onto an object, where the structural light SL hasstripe pattern, as shown in FIG. 7. The camera module 12_r may capturean image of the structural light SL projected onto the object, andcalculate depth information of the object (using the triangularmeasuring method) according to curveness of the structural light SL onthe object, so as to obtain a 3D image related to the object.

Specifically, the structural light module 12_t comprises a pulse signalgenerator 120, a light-emitting unit 122 and a diffraction unit 124. Thelight-emitting unit 122 may be a light-emitting diode (LED) or a laseremitting unit. The diffraction unit 124 may be a diffraction opticalelement (DOE). The pulse signal generator 120 is configured to generatea pulse signal pml. The light-emitting unit 122 is coupled to the pulsesignal generator 120, to receive the pulse signal pml and generate/emita first light L1 to the diffraction unit 124 according to the pulsesignal pml. Diffraction effect would be formed on the first light L1 inthe diffraction unit 124, and the structural light SL is generated.Moreover, the pulse signal pm1 is a pulse modulated signal, i.e., thepulse signal pml may be regarded as square waves with small duty cycle.In addition, when the light-emitting unit 122 emits the first light L1,the light-emitting unit 122 would have a large emission power.Specifically, a duty cycle of the pulse signal pml may be 1/1000 ingeneral, and not limited herein. As long as the duty cycle of the pulsesignal pml is less than 1/50, requirements of the present applicationare satisfied. In addition, an emission power of the light-emitting unit122 is between 4 watts and 5 watts in general, and not limited herein.As long as the emission power of the light-emitting unit 122 is greaterthan 4 watts, requirements of the present application are satisfied. Inother words, the light-emitting unit 122 may be regarded as emitting astrong light instantaneously, which is similar to a photoflash of ageneral camera) , so as to enhance a light signal strength related tothe structural light SL received by the camera module 12_r, such thatthe light signal related to the structural light SL has immunity againstthe ambient light, to improve over disadvantages of the prior art.

In another perspective, the camera module 12_r includes a light-sensingpixel array 14 and a lens 18. The light-sensing pixel array 14,receiving a reflected light corresponding to the structural light SL,comprises a plurality of light-sensing pixel circuits 16. The outputsignals of the light-sensing pixel circuits 16 may correspond to pixelvalues of the image captured by the camera module 12_r. The circuitstructure and operational mechanism of the light-sensing pixel circuit16 are not limited. For example, please refer to FIG. 2 and FIG. 3. FIG.2 is an equivalent schematic circuit diagram of the light-sensing pixelcircuit 16 according to an embodiment of the present application. FIG. 3is a timing diagram of the light-sensing pixel circuit 16. Thelight-sensing pixel circuit 16 comprises a light-sensing component PDand photoelectric readout circuits 16_1, 16_2. Both the photoelectricreadout circuits 16_1 and 16_2 include transmission gates, resettransistors, output transistors and read transistors. The transmissiongates are coupled to the light-sensing component PD. Gates of the resettransistors receive a reset signal Reset. Gates of the read transistorsreceive a row select signal ROW. The transmission gates of thephotoelectric readout circuits 16_1 and 16_2 receive signals TX1 andTX2, respectively. The transmission gate, the reset transistor and theoutput transistor of the photoelectric readout circuit 16_1 areconnected to a node FD_1. The transmission gate, the reset transistorand the output transistor of the photoelectric readout circuit 16_2 areconnected to a node FD_2. In addition, the light-sensing pixel circuit16 also includes an anti-blooming transistor, and a gate of theanti-blooming transistor receives a signal TX4.

Operational mechanism of the light-sensing pixel circuit 16 is describedas follows. When the pulse signal pm1 is high, the light-emitting unit122 emits the first light L1. When the light-emitting unit 122 emits thefirst light L1, the transmission gate of the photoelectric readoutcircuit 16_1 is conducted. In an embodiment, a conduction time intervalT1 of the transmission gate within the photoelectric readout circuit16_1 is wider than a time interval T4 of the pulse signal pml beinghigh, i.e., the conduction time interval of the transmission gate withinthe photoelectric readout circuit 16_1 is longer than an emitting timeinterval of the light-emitting unit 122. When the transmission gate ofthe photoelectric readout circuit 16_1 is conducted (i.e., the signalTX1 is high), i.e., within the conduction time interval T1, thelight-sensing component PD receives the first light L1 and the ambientlight, and the transmission gate of the photoelectric readout circuit16_1 may drain out the photocharge generated by the light-sensingcomponent PD because of receiving the first light L1 and also theambient light and store the photocharge at the node FD_1. In anotherperspective, when the light-emitting unit 122 does not emit light (i.e.,the pulse signal pm1 is low), the transmission gate of the photoelectricreadout circuit 16_2 may be conducted in a short time (the signal TX2 ishigh). At this time, the light-sensing component PD receives the ambientlight only, and the transmission gate of the photoelectric readoutcircuit 16_2 may drain out the photocharge generated by thelight-sensing component PD because of receiving the ambient light andstore the photocharge at the node FD_2. When the read transistors of thephotoelectric readout circuits 16_1 and 16_2 are conducted, the readtransistor the photoelectric readout circuit 16_1 outputs an outputsignal Pout1 (which is related to the first light L1 and the ambientlight), and the read transistor of the photoelectric readout circuit16_2 outputs an output signal Pout2 (which is related to the ambientlight only). The pixel value corresponding to the light-sensing pixelcircuit 16 is a subtraction result of the output signal Pout1 and theoutput signal Pout2 (e.g., Pout1-Pout2). Therefore, an effect of theambient light may be eliminated in the pixel value of the light-sensingpixel circuit 16. In addition, when the transmission gates of thephotoelectric readout circuits 16_1 and 16_2 are not conducted, theanti-blooming transistor of the light-sensing pixel circuit 16 isconducted (the signal TX4 is high). The light-sensing pixel circuit 16would drain out the photocharge of the light-sensing component PD causedby receiving the ambient light, to maintain normal operation.

After the light-emitting unit 122 emits the instantaneous strong light,it requires a time for the light-emitting unit 122 to rest, and then thelight-emitting unit 122 is able to emit light again. That is, the dutycycle of the pulse signal pml maybe too small such that a light strengthcorresponding to the structural light SL received by the camera module12_r is insufficient. Thus, in an embodiment, the structural lightmodule may comprise two light-emitting units. The two light-emittingunits may emit lights alternatively, so as to enhance the strengthcorresponding to the structural light received by the camera module12_r. Furthermore, the two light-emitting units may emit lights withdifferent wavelengths. Since the different wavelengths have variousrefractions, the structural light generated by passing through thediffraction unit may have denser stripe pattern, and resolution of the3D image is further enhanced.

Specifically, please refer to FIG. 4. FIG. 4 is a schematic diagram of a3D image system 40 according to an embodiment of the presentapplication. The 3D image system 40 is similar to the 3D image system10, and thus, same components are denoted by the same symbols. Differentfrom the 3D image system 10, the structural light module 42_t of the 3Dimage system 40 comprises another light-emitting unit 422, in additionto the light-emitting unit 122. The light-emitting unit 422 receives apulse signal pm2 to generate a second light L2. The second light L2 andthe first light L1 may have different wavelengths. Similarly, a dutycycle of the pulse signal pm2 may be 1/1000 (or less than 1/50). Anemission power of the light-emitting unit 422 maybe between 4 watts and5 watts (or greater than 4 watts). In addition, the first light L1 andthe second light L2 pass though the diffraction unit 124, in which thediffraction effect is formed, such that a structural light SL′ isgenerated. Since the first light L1 and the second light L2 have thedifferent wavelengths, the stripe pattern of the structural light SL′ isdenser. As shown in FIG. 8, a strip light spl represents the structurallight corresponding to the first light L1, and a strip light sp2represents the structural light corresponding to the second light L2.

In addition, a camera module 42_r of the 3D image system 40 comprises alight-sensing pixel array 44. The light-sensing pixel array 44 comprisesa plurality of light-sensing pixel circuits 46. The circuit structureand operational mechanism of the light-sensing pixel circuit 46 are notlimited. For example, please refer to FIG. 5 and FIG. 6. FIG. 5 is anequivalent schematic circuit diagram of the light-sensing pixel circuit46 according to an embodiment of the present application. FIG. 6 is atiming diagram of the light-sensing pixel circuit 46. The light-sensingpixel circuit 46 is similar to the light-sensing pixel circuit 16, andthus, same components are denoted by the same symbols. Different fromthe light-sensing pixel circuit 16, the light-sensing pixel circuit 46further comprises the photoelectric readout circuit 46_3. The circuitstructure of the photoelectric readout circuit 46_3 is the same as whichof the photoelectric readout circuits 16_1 and 16_2, where atransmission gate of the photoelectric readout circuit 46_3 receives asignal TX3. Similarly, when the light-emitting unit 422 emits the secondlight L2, the transmission gate of the photoelectric readout circuit46_3 is conducted. The light-sensing component PD receives the secondlight L2 and the ambient light, and the transmission gate of thephotoelectric readout circuit 46_3 may drain out the photochargegenerated by the light-sensing component PD because of receiving thesecond light L2 and the ambient light and store the photocharge a nodeFD_3. Similarly, when the light-emitting units 122 and 422 do not emitlight (i.e., the pulse signals pm1 and pm2 are low), the transmissiongate of the photoelectric readout circuit 16_2 may be conducted in ashort time (the signal TX2 is high). At this time, the light-sensingcomponent PD receives the ambient light only, and the transmission gateof the photoelectric readout circuit 16_2 may drain out the photochargegenerated by the light-sensing component PD because of receiving theambient light and store the photocharge at the node FD_2. When the readtransistors of the photoelectric readout circuits 16_1, 16_2 and 46_3are conducted, the read transistor the photoelectric readout circuit16_1 outputs an output signal Pout1 (which is related to the first lightL1 and the ambient light), the read transistor of the photoelectricreadout circuit 16_2 outputs an output signal Pout2 (which is related tothe ambient light only), and the read transistor of the photoelectricreadout circuit 46_3 outputs an output signal Pout3 (which is related tothe second light L2 and the ambient light). The pixel valuecorresponding to the light-sensing pixel circuit 46 is a sum of theoutput signal Pout1 and the output signal Pout3 minus twice of theoutput signal Pout2 (i.e., Pout1+Pout3−2*Pout2), such that an effect ofthe ambient light may be eliminated. In addition, the conduction timeintervals of the transmission gates within the photoelectric readoutcircuits 16_1, 16_2 are wider than pulse widths of the pulse signals pm1and pm2, i.e., the conduction time intervals of the transmission gateswithin the photoelectric readout circuits 16_1, 16_2 are longer than theemitting time intervals of the light-emitting units 122, 422. Inaddition, the conduction time interval T1 of the transmission gatewithin the photoelectric readout circuit 16_1 and the conduction timeinterval T8 of the transmission gate within the photoelectric readoutcircuit 46_3 are separated by a time blank T7. The rest operationalmechanism is referred to the paragraph stated in the above, which is notnarrated herein for brevity.

In addition, the 3D image system of the present application may bedisposed with an electronic device. Please refer to FIG. 9. FIG. 9 is aschematic diagram of an electronic device 9 according to an embodimentof the present application. The electronic device 9 comprises a 3D imagesystem 90, where the 3D image system 90 may be realized by the 3D imagesystem 10 or the 3D image system 40.

Notably, the embodiments stated in the above are utilized forillustrating the concept of the present invention. Those skilled in theart may make modifications and alterations accordingly, and not limitedherein. For example, the duty cycles of the pulse signals pm1 and pm2may be changed randomly (i.e., the duty cycles of the pulse signals pm1and pm2 are time variant). For example, after the pulse signal generator120 generates one pulse, the pulse signal generator 120 may generate asubsequent pulse (N+n) period of time later, where N may be a largeinteger and n may be a random number. Therefore, the structural lightscorresponding to different electronic devices are prevented frominterfering each other. Please refer to FIG. 12, FIG. 12 illustrateswaveforms of pulse signals pmA, pmB and signals TXA, TXB of electronicdevices A, B. The pulse signal pmA is the pulse signal received by thelight-emitting unit within the electronic device A. The pulse signal pmBis the pulse signal received by the light-emitting unit within theelectronic device B. The signal TXA is the signal received by thetransmission gate within the photoelectric readout circuit of thelight-sensing pixel circuit within the electronic device A. The signalTXB is the signal received by the transmission gate within thephotoelectric readout circuit of the light-sensing pixel circuit withinthe electronic device B. As shown in FIG. 12, when the duty cycles ofthe pulse signals are randomly generated, the light-emitting timecorresponding to the light-emitting unit of the electronic device A andwhich of the electronic device B would be interleaved. The conductiontime corresponding to the transmission gate of the electronic device Aand which of the electronic device B would be interleaved as well. Thus,the light signals related to the structural lights from the electronicdevice A and the electronic device B would not interfere each other.

In addition, the structural light module of the present application maycomprise a plurality of light-emitting unit. Please refer to FIG. 10 andFIG. 11, FIG. 10 is a schematic diagram of a structural light modulec2_t according to an embodiment of the present application. FIG. 11 is aschematic diagram of a light-sensing pixel circuit d6 corresponding tothe structural light module c2_t. The structural light module c2_tcomprises the light-emitting units 122 and 122_1-122_K, which emit lightat different time instant. The light-sensing pixel circuit d6 comprisesphotoelectric readout circuits d6_1-d6_K′ and d6_B. The circuitstructure of the photoelectric readout circuits d6_1-d6_K′ and d6_B maybe the same as which of the photoelectric readout circuits 16_1, 16_2 or46_3 stated in the above. The conduction time intervals of thetransmission gate within the photoelectric readout circuits d6_1-d6_K′(K′ may represent K+1) are corresponding to the emitting time intervalsof the light-emitting units 122, 122_1-122_K. The photoelectric readoutcircuits d6_1-d6_K′ output the output signals Pout1-Pout K′. The outputsignals Pout1-Pout K′ are related to the lights emitted from thelight-emitting units 122, 122_1-122_K and the ambient light. Thetransmission gate of the photoelectric readout circuit d6_B is conductedwhen all the light-emitting units 122, 122_1-122_K do not emit light,which means that the photoelectric readout circuit d6_B only reads thephotocurrent caused by the ambient light, i.e., the output signal PoutBoutputted by the photoelectric readout circuit d6_B is only related tothe ambient light. In this case, the pixel value corresponding to thelight-sensing pixel circuit d6 may be Pout1+ . . . +PoutK′−K′*PoutB.

In summary, the light-emitting unit within the structural light moduleof the present application receives the pulse signal, which is pulsemodulated, and emits instantaneous strong light, such that the emittedstructural light has immunity against the ambient light, to improve overdisadvantages of the prior art.

The foregoing is only embodiments of the present application, which isnot intended to limit the present application. Any modificationfollowing the spirit and principle of the present application,equivalent substitutions, improvements should be included within thescope of the present invention.

What is claimed is:
 1. A three-dimensional (3D) image system,characterized by, comprising: a structural light module, configured toemit a structural light, wherein the structural light module comprises:a pulse signal generator configured to generate a first pulsed signal;and a first light-emitting unit, wherein the first light-emitting unitconfigured to receive the first pulse signal and emit a first lightaccording to the first pulse signal, a duty cycle of the first pulsesignal is less than a specific value, an emission power of the firstlight-emitting unit is greater than a specific power, and the firstlight has a first wavelength.
 2. The 3D image system as claim 1,characterized in that, the duty cycle of the first pulse signal is lessthan 1/50.
 3. The 3D image system as claim 1, characterized in that, theemission power of the first light-emitting unit is greater than 4 watts.4. The 3D image system as claim 1, characterized in that, the structurallight module comprises at least a second light-emitting unit, the atleast a second light-emitting unit receives at least a second pulsesignal and emits at least a second light according to the at least asecond pulse signal, at least a duty cycle of the at least a secondpulse signal is less than the specific value, an emission power of theat least a second light-emitting unit is greater than the specificpower, and the at least a second light has at least a second wavelength,respectively.
 5. The 3D image system as claim 4, characterized in that,the first wavelength and the at least a second wavelength are different.6. The 3D image system as claim 4, characterized in that, the dutycycles of the first pulse signal and the at least a second pulse signalare time variant.
 7. The 3D image system as claim 1, characterized inthat, the duty cycle of the first pulse signal is time variant.
 8. Anelectronic device, characterized in that, comprising a three-dimensionalimage system, wherein the three-dimensional image system comprises: alight module, comprising: a pulse signal generator configured togenerate a first pulsed signal; and a first light-emitting unit, whereinthe first light-emitting unit configured to receive the first pulsesignal and emit a first light according to the first pulse signal, aduty cycle of the first pulse signal is less than a specific value, anemission power of the first light-emitting unit is greater than aspecific power, and the first light has a first wavelength.
 9. Theelectronic device as claim 8, characterized in that, the duty cycle ofthe first pulse signal is less than 1/50, and the emission power of thefirst light-emitting unit is greater than 4 watts.
 10. The electronicdevice as claim 8, characterized in that, the light module comprises atleast a second light-emitting unit, the at least a second light-emittingunit receives at least a second pulse signal and emits at least a secondlight according to the at least a second pulse signal, at least a dutycycle of the at least a second pulse signal is less than the specificvalue, an emission power of the at least a second light-emitting unit isgreater than the specific power, and the at least a second light has atleast a second wavelength, respectively.
 11. The electronic device asclaim 10, characterized in that, the first wavelength and the at least asecond wavelength are different.
 12. The electronic device as claim 10,characterized in that, the duty cycles of the first pulse signal and theat least a second pulse signal are time variant.
 13. The electronicdevice as claim 8, characterized in that, the duty cycle of the firstpulse signal is time variant.
 14. A structural light module, configuredto emit a structural light, wherein the structural light modulecomprises: a pulse signal generator configured to generate a firstpulsed signal for driving a first light-emitting unit to emit a firstlight, a duty cycle of the first pulse signal is less than a specificvalue, an emission power of the first light-emitting unit is greaterthan a specific power, and the first light has a first wavelength. 15.The structural light module as claim 14, characterized in that, the dutycycle of the first pulse signal is less than 1/50.
 16. The structurallight module as claim 15, characterized in that, the emission power ofthe first light-emitting unit is greater than 4 watts.
 17. Thestructural light module as claim 14, characterized in that, the pulsesignal generator is configured to generate a second pulsed signal fordriving a second light-emitting unit to emit a second light.
 18. Thestructural light module as claim 17, characterized in that, a duty cycleof the second pulse signal is less than the specific value, an emissionpower of the second light-emitting unit is greater than the specificpower, and the second light has at least a second wavelength.